Journal of Energy History Revue d’histoire de l’énergie

AUTHOR Finn Harald Sandberg Condeeps. The Dinosaurs of the Norwegian Museum, () Abstract POST DATE When oil was found in water depths larger than 150 meters 03/06/2019 in the North Sea in the 1970s, a new and revolutionary ISSUE NUMBER concept was needed to be able to support deck structures JEHRHE #2 for production of petroleum. Norwegian entrepreneurs SECTION introduced a new design based on their experience with Energy sources large structures of concrete. The design, named Condeep, KEYWORDS was developed. For a period of 25 years this design became Oil, Heritage, Gas, Dam the dominant support structure for platforms placed in DOI water depths up to 300 meters. By early 1990s new tech- in progress nology had been developed and deeper waters were being challenged. The Condeeps could no longer with- TO CITE THIS ARTICLE stand the competition and the industry had no longer Finn Harald Sandberg, use for the giant structures. However, the world needs a “Condeeps. The Dinosaurs of symbol or monument over a very special period that may the North Sea”, Journal of come to an end sooner than we know. One such plat- Energy History/Revue form may be well suited for a UNESCO world heritage d’Histoire de l’Énergie – the Draugen platform in the Norwegian Sea. This article [Online], n°2, published 03 introduces the reasoning behind such a suggestion. juin 2019, consulted XXX, URL: http://energyhistory.eu/ Plan of the article node/136. → Concrete platforms for the North Sea → Designing Condeeps → Preserving one of the dinosaurs of the North Sea: why and how

ISSN 2649-3055 JEHRHE #2 | ENERGY SOURCES P. 2

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1 When Norway became an oil producing coun- try towards the end of the 1960s, only a few people expected that a Norwegian entrepre- neur company could become one of the largest subcontractors to the upcoming exploration of the North Sea – using concrete as a material in exceptional and giant structures.

2 Realizing what a great influence the oil indus- try has had for the development of economic and social life in Norway there have been sev- eral ideas how to preserve at least one of these structures for the future – when the fossil fuel

era comes to an end. One platform - in my Figure 1: The Zakarias dam (completed 1969). Photography mind - Draugen, could be a strong candidate by Vidar Iversen [CC BY-SA 3.0]. for becoming an international monument and possibly gain status as a UNESCO world heritage In Norway concrete has been used as the main 4 status. Having spent more than 30 years in the material in dams built for producing electricity. Norwegian oil industry I have seen most of the Until the mid-1950s concrete was the dominat- technical progress that has been taking place. ing material and many companies were involved The most important structures are the huge in the big projects in the Norwegian mountains Condeeps (abbreviated from Concrete Platform (fig. 1). for Deep Waters). The time of the fossil fuels may be obsolete within this century, the petroleum A few years after oil was found in the Norwegian 5 industry has been the basis for the development part of the North Sea, Norwegian Contractors of modern Norway and the concrete structures (NC) was formed in 1973 as a Joint Venture of are unique pieces of design and construction. three large contractors and their idea was to utilize their joint experience, competence and resources and take advantage of the country’s CONCRETE PLATFORMS FOR THE NORTH SEA special topography with deep fjords and plenty 3 The first traces of a material that can have of raw material to produce structures special- some resemblance to concrete dates back 20 ized for this new industry.3 000 years. It was however the Romans, a little more than 2000 years ago, who really devel- The first ideas using concrete for oil extraction 6 oped the knowledge and competence of how were launched in 1970 by two of the co-founding to create huge buildings based on using ashes companies – and a concrete floatable platform from volcanoes as an important ingredient. The support was introduced (picture) shortly after. volcano ashes used in concrete were called poz- zolans after the city Pozzuoli, close to Naples A total of 17 giant structures were built in Norway 7 and Vesuvius, where the material was first col- by Norwegian Contractors (and the founding lected.1 Two hundred years ago, an industrial companies) during a period of 25 years. Most product named Portland cement was introduced of them were Condeeps based on the princi- overtaking the market from the natural poz- ple of standing securely on the sea bed only by zolans.2 the force of its own weight – a so called gravi- ty-based structure (GBS). 1 Ruth Whitehouse, John Wilkins, The Making of Civilization. History Discovered Through Archaeology (New York: Alfred A. Knopf, 1986). 2 Frederick Measham Lea, The Chemistry of Cement and 3 Øyvind Steen, På dypt vann. Norwegian Contractors Concrete 3rd ed. (London: Arnold, 1970). 1973 – 1993 (Oslo: Norwegian Contractors, 1993), 16. JEHRHE #2 | ENERGY SOURCES P. 3

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Figure 2: Høyer-Ellefsen’s first suggestion for a concrete platform structure (1970) – an early Condeep experiment. Source: Øyvind Steen, På dypt vann. Norwegian Contractors 1973 – 1993 (Oslo: Norwegian Contractors, 1993), 7.

Figure 3: Table listing the 17 concrete platforms produced in Norway by Norwegian Contractors between 1973 and 1995. Source: Steen, På dypt vann. Norwegian Contractors 1973 – 1993 (Oslo : Norwegian Contractors, 1993). JEHRHE #2 | ENERGY SOURCES P. 4

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Figure 4: The remains of the concrete platforms left on Frigg field in the North Sea. © Total E&P Norge / Norwegian Petroleum Museum.​​

8 Of the listed structures Ekofisk, the Brents and been made available for the NPM. Many of these the Friggs have already been decommissioned – are made publicly available at the site https:// but the concrete structures are left in the fields digitaltmuseum.no. – more than 3000 pictures with the deck structures removed (fig. 4).4 can be found using only Norwegian Contractors as search criterion. 9 The Norwegian Petroleum Museum (NPM) coop- erates with The Norwegian Oil and Gas Archives DESIGNING CONDEEPS (NOAGA) in documenting many of the large devel- opments on the Norwegian Continental Shelf. So From the list above one finds that the Condeeps 11 far five large Industrial Heritage Projects have came in many different shapes both in height been completed (Ekofisk, Frigg, Statfjord, Valhall and number of legs. Most of them were never and Draugen). meant to be removed, but some are designed for being towed back to the coast to be destructed. 10 In addition, NOAGA has received the complete The above mentioned Draugen is one of these. archives from Norwegian Contractors for the period between 1973 and 1995 when the com- There were several reasons for starting to build 12 pany was in existence. Altogether there is 16 concrete platforms in the North Sea. In the shelf meters of interesting material to be found. early 1970s, several huge discoveries of oil on All films and photos from the building, transport the British and Norwegian continental shelf, and installations of the concrete platforms have Beryl, Brent, Ninian and Statfjord were made, to name the largest. At that time, there were no 4 Adam Vaughan, “Shell begins huge task of decommis- marine structures such as “jackets” (large steel sioning Brent oil rigs”, The Guardian, 06/02/2017. Url : https:// www.theguardian.com/business/2017/feb/06/shell-decom- framework structures fig. 5) or floaters suitable missioning-… (accessed 17/05/2019) for building production facilities of 120m - 150m JEHRHE #2 | ENERGY SOURCES P. 5

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connected to the nearest pipeline as one moved further from the coast. In the North Sea, the most promising areas were situated far from the coastline both in the UK and in Norway and there were no pipelines available.

The basic conditions and the marine environ- 14 ment are more demanding in the North Sea. Piling equipment designed for installation of steel platforms in the Gulf of Mexico, was inad- Figure 5: An example of a steel jacket – supporting structure equate for the seabed in the northern North Sea for oil producing facility in the North Sea. Source: Puput Aryanto with hard sand and clay layers formed by the Risanto, Introduction to Offshore Oil and Gas Surface Facilities (2015). URL: https://www.slideshare.net/PuputAryanto/ glaciers during the ice age. Without pipelines for introduction-to-offshore-oil-and-gas-surface-facilities. export, oil storage and offshore loading to tank- ers were necessary to uphold a consistent pro- duction under adverse weather conditions. There water depth in the North Sea. In addition, there were thus many challenges and opportunities was no infrastructure in the form of pipelines for that the industry faced when developing large exporting oil and gas from the platforms. oil fields in the North Sea. Norwegian indus- try, and Norwegian entrepreneurs, were active 13 In the 1960s the Gulf of Mexico was the refer- and inventive in promoting ideas and developing ence point for offshore oil and gas production. suggestions for new concepts. Høyer-Ellefsen However, there were several conditions that were and Akergruppen (two of the companies forming different in the North Sea. One of these differ- Norwegian Contractors in 1973) were involved in ences was that the production rate was con- a collaboration that proved to be very success- sistently higher from the North Sea areas. This ful resulting in the Condeep platform design. required systems for the UK and the Norwegian The biggest challenge was with the oil compa- sectors with more equipment and consider- nies that had to choose solutions and methods ably increased weight. Steel platforms at that that neither supplier nor customer had full scale time had to have the deck installed offshore experience with. after the support structure was placed on the seabed. Cranes with lifting capacity of 10,000 - The reasons for the operating companies Mobil 15 12,000 tons, as we know it today, did not exist and Shell in 1973 to develop the Beryl and Brent then. It was therefore a huge task to transport oilfields on the UK shelf, using concrete platforms modules of 800-1000 tons offshore, lift them were to avoid the expensive and time-consum- into place and connect the modules that could ing work of installing piles to secure the steel weigh a total of 20,000-30,000 tons. Typically, jacket. In addition, the platform had sufficient in the Gulf of Mexico, lifts of 500 to 5000 tons buoyancy to carry the deck with the necessary were covered. Second, weather conditions which facilities for processing the petroleum from an were constantly much worse in the North Sea, inshore construction site. Thus, the deck could even though the Mexican Gulf had its challenges be equipped and coupled up in a controlled envi- during the hurricane season. Third and last, the ronment and the finishing offshore was substan- generally larger distance to shore resulted in tially simplified. And last but not least, when increased demands for logistics arrangements the platform was set on the seabed it no longer and space for equipment storage on board. The needed buoyancy and the cavity in the concrete development of offshore platforms in the Gulf platform would serve as oil storage (fig. 6). of Mexico had started with facilities near shore and pipeline installation became an integral The first three Condeeps were delivered to Mobil 16 part of field developments. The platforms were and Shell in 1975 for the British continental shelf. JEHRHE #2 | ENERGY SOURCES P. 6

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Figure 6: Troll A, the last Condeep. Photography Øyvind Hagen / .

It also meant the start of an industrial adventure company C.G. Doris in May 1971 to build an ‘oil for Norwegian suppliers. The concrete substruc- container of concrete’ that could hold one million tures were built in Norway and the deep fjords barrels of crude oil.5 Two years and one month on the west coast were suitable for mating with later the structure now known as the Ekofisk the deck and tow. This gave Norwegian shipyards tank was towed to the oil field.6 Within that a natural advantage for building top sides. The time span the companies also had to develop a effects of this scheme were huge. Engineering site that should be the breeding ground for the companies, technology development, subcon- Norwegian concrete dinosaurs for more than 20 tractors, consultants and research institutions years. were engaged because the business was con- ducted in Norway. If Mobil and Shell had focused The next month (July 13, 1973) the first con- 18 on steel platforms for Beryl and Brent, construc- tract for the new concept of an tion work would not have ended in Norway and (Condeep) made of concrete was signed.7 It was Norwegian industry would not have had the Mobil North Sea Limited who wanted to use this same development opportunities. When Mobil type of platform for their Beryl field develop- found the Statfjord field in 1974, they were build- ment. Two weeks later Shell ordered a similar ing the Beryl platform and they chose the same platform for their Brent field development also solution for the Statfjord development. in the UK sector of the North Sea. The Beryl and Brent platforms were built in Stavanger and 17 The Ekofisk tank was the first of the giant con- have been operating on the British side of the crete structures to be placed on the seabed of border. Brent B was abandoned in 2016 and the the Norwegian Continental shelf. It was not a decommissioning started early in 2017. The Beryl Condeep, but it made it possible to establish a platform is still operating. company and a construction yard for future oil related activities. The two Norwegian entrepre- 5 Steen, På dypt vann (cf. note 3). neur companies Ingeniør F. Selmer A/S and A/S 6 Ibid. Høyer-Ellefsen were contracted by the French 7 Ibid. JEHRHE #2 | ENERGY SOURCES P. 7

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Figure 7: The Frigg field in the North Sea – the border between UK and Norway is indicated with a green line. © Total E&P Norge / Norwegian Petroleum Museum.

19 The next field to be using concrete platforms The Gullfaks A was the first platform to be 100% 21 was the French operated Frigg field where the Norwegian owned and operated.8 The Gullfaks gas reservoir stretched out to both sides of the offshore field was owned jointly by the three British/Norwegian border. The treatment plat- Norwegian oil companies that existed at that form TP1 was designed by Sea Tank Company time. Statoil was the operator with in Paris and was built in Scotland, The Manifold and Saga as partners. The field has used three Compression Platform MCP-01, designed by Condeep platforms for the development and the Doris Engineering was built in Sweden. This plat- Gullfaks C was the first platform to be fitted with form was decommissioned in 2006. Two Frigg concrete skirts (to penetrate the sea bottom to platforms were the only concrete platforms to create a stable foundation), and it is also the be built in Åndalsnes and only one was of the heaviest structure to be moved by man (1,5 mil- Condeep-design, The Treatment Compression lion metric tons). Platform 2 - TCP2. The TP1 and the TCP2 were physically connected with a bridge crossing the The Sleipner A platform was the only platform 22 Norwegian UK border (fig. 7). to collapse during construction. On a beauti- ful August morning in 1991 the concrete struc- 20 The three platforms for the Statfjord field, all ture sank during a submergence test In the Condeeps, have been operating in one of the Gandsfjord close to Stavanger. One of the inter- world’s largest offshore oil fields since 1979. On nal cells could not withstand the pressure from October 12th, 1983 they produced a record volume being submerged lower than the depth at the of 870 000 barrels of oil. Based on the present destination in the North Sea and water poured oil price of 50 - 60 USD per barrel, that means roughly 2 million dollars per hour! 8 Harald Tønnesen, Gunleiv Hadland, Oil and Gas Fields in Norway. Industrial Heritage Plan (Stavanger: Norwegian Petroleum Museum, 2011). JEHRHE #2 | ENERGY SOURCES P. 8

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Figure 8: The Heidrun platform. Photography by Harald Pettersen / Equinor.

Figure 9: The Norne, a Floating Production, Storage and Offloading (FPSO)​​​​ unit​, shaped as a ship. Photography by Kenneth Engelsvold / Equinor.

in. On the way down to the bottom of the fjord prestressed concrete.10 The platform was the the structure imploded creating a soundwave first to produce oil north of the 62nd latitude that was registered as a small earthquake at a and the only platform north of this borderline geological center in Bergen, several kilometers to be standing directly on the sea bottom. The away.9 other platforms are floating structures either semi-submersible structures (fig. 8) or ships 23 The Draugen was built with only one leg – a (fig. 9). monotower design. The platform and its designer Olav Olsen were in 1995 awarded the The Troll A – the tallest structure to be moved 24 Gustave Magnel Golden medal for a structure in by mankind 472 meters from the lowest point

10 The letter from AIG-Stiching declaring the winner 9 ”Havariet av SLEIPNER A GBS, August 1991”, Presentation was sent September 7th 1994 – the ceremony was held in at the Petroleum Safety Authority Norway conference (PTIL) 1995. See : https://draugen.industriminne.no/en/2018/05/14/ 2007. medal-award-for-draugen-… JEHRHE #2 | ENERGY SOURCES P. 9

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Figure 10: The Troll A platform ready for tow out to the field. Source: https://i.redd.it/8w98q0thaoa01.jpg.

on the concrete skirts to the top of flare boom I will not be surprised if such structures will It was also the last of the giants to be built for inspire architects to create new ideas for exam- the North Sea (fig. 10). ple churches …”11

25 When it was placed on the sea bottom at a depth Even the interior of the Troll A platform lends 27 of more than 300 meters in 1995 it meant the end itself to giving an impression of a large church. of an era. Similar structures have been used for Picture to the left is from a concert given in 2006 the oil industry in other parts of the world such by the song artist Katie Melua at the bottom of as east of Canada (Hibernia and Hebron) and the Troll A platform (the deepest concert ever offshore the Pacific coast of Russia (Sakhalin). held).12 But not only inside – the top of the plat- The Condeeps are fantastic structures that not form Draugen as it can be seen above the water only were meant to support the oil factories, but does seem to copy the Stavanger Cathedral from also to offer temporary storage for the black gold. the 12th century – both internally and externally.

Should we preserve one of the dinosaurs 28 PRESERVING ONE OF THE DINOSAURS OF THE for eternity? – It is technically possible but NORTH SEA: WHY AND HOW extremely expensive! Indications that have been 26 In his book Leviathan (1979), Alfred Hauge used discussed among experts, range between 1 to the words “Condeep Cathedral” and “petrodome” 3 billion American dollars, only for ‘picking it to describe the shape of these giant structures up’ offshore, transporting and placing it close and one can sense some resemblance with to shore. What it will cost to prepare it and cathedrals. Hauge’s fascination with these struc- Leviathan tures was also present in an essay from 1980: 11 Alfred Hauge, (Oslo: Gyldendal Norsk Forlag, 1979). “So beautiful it is with the tall slender shafts 12 Trailer here: https://www.youtube.com/watch?v=o5W- as they are called; resembling huge lighthouses. rk7GRiS4 (accessed 29 May 2019) JEHRHE #2 | ENERGY SOURCES P. 10

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Figure 11a: Sagrada Familia (Barcelona, Spain). Source: Atlas Figure 11b: Sletringen Lighthouse (Norway). Photography by Obscura. Odd Einar Helmersen Helge Høifødt [Public domain].Atlas Obscura.

Figure 11c: The Nidaros Cathedral (Trondheim, Norway). Photography by Photo: Zairon [CC BY-SA 3.0]. JEHRHE #2 | ENERGY SOURCES P. 11

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Figure 11d: Troll A. Norwegian Contractors / Norwegian Petroleum Museum.

Figure 11e: Katie Melua at concert in the Troll A platform. Photography by Kjell Alsvik. JEHRHE #2 | ENERGY SOURCES P. 12

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Figures 12: The Stavanger Cathedral and The Draugen platform. Photographies by Helge Høifødt [Public domain], and A/S Norske Shell / Norwegian Petroleum Museum. JEHRHE #2 | ENERGY SOURCES P. 13

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presenting it as an industrial heritage has not area’s integrity is also dependent on the been evaluated. But as a monument of the era delimitation capturing all necessary elements. that brought Norway immense wealth in money • Authenticity. The object or the environment’s and technological competence it should be an degree of origin or authenticity is an expres- idea to follow up at least. sion of authenticity. • Protection and management. World Heritage 29 The importance of these structures for the Sites should be subject to long-term formal development of deep-sea oil producing tech- or contractual protection against measures nology and the growth of Norway’s and other oil or threats that may adversely affect the uni- producing nations’ position today cannot how- versal values. ever be underestimated. It is therefore relevant • The areas must be clearly defined and where to ask if one of these giant structures should be necessary be surrounded by a buffer zone preserved for future generations and be used as with its own provisions ensuring that qual- an arena to explain to the general public all the ities within the world heritage area are not technical aspects of deep-sea natural exploita- adversely affected. tion. • The management of the area will follow a reversal plan that ensures coordinated fol- 30 UNESCO World Heritage Sites is a program under low-up of measures that are best for the area. the auspices of UNESCO for the preservation of • Human activity within world heritage sites a variety of natural and cultural sites on Earth. must be ecologically and culturally sustainable. The places, such as a forest, a mountain, a lake, a desert, a monument, a building, a complex, • Local support. A world heritage nomination or a city, are selected because of their cultural will not be approved without it being anchored importance or for the natural history of human- in the community. ity. UNESCO’s World Heritage List is the most Why an oil platform? Through more than fifty 32 widely used environmental treaty in the world. years of activity on the Norwegian continental The program was launched on November 16, 1972, shelf (NCS), the petroleum industry has grown when UNESCO adopted a Convention for the to become Norway’s most important industry. Protection of Cultural and Natural Heritage. 1092 The exploration and production of oil and gas places were listed on March 2019, 845 of which has been the most important reason for the are cultural heritage sites, 209 natural heritage global development of modern society for more sites and 38 a mixture of the two categories.13 than 150 years.

31 Industrial cultural monuments are part of the In Norway the industry directly and indirectly 33 cultural heritage sites but represent only about employs around 300 000 people, while a high 5% of these. Requirements for world heritage tax rate and the state’s direct ownership con- status are: tribute to the bulk of the value creation on NCS. • Outstanding universal value. An area or object Many of the contracts for building modules and has outstanding universal value if it represents production units for the Norwegian Continental in the global context the best example within Shelf have been and still are being placed all a cultural or natural subject of a particular around the globe. Of the gross domestic prod- format. uct in Norway in 2014, the state calculated that • Integrity. All world heritage objects or areas it amounted to NOK 958.9 billion. That is about must contain all elements necessary to one third of the 3 167 billion that are created in express the prominent universal values. The Norway for a year. It includes both oil and gas production, investments on platforms and ships, as well as all those working on petroleum. 13 UNESCO World Heritage. Url: https://whc.unesco.org/ en/list/ (accessed 02/04/2019) JEHRHE #2 | ENERGY SOURCES P. 14

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34 In April 2001, the Directorate for Cultural years. The unique monotower structure was Heritage of Norway expressed in a letter to the also designed to be physically removed from Norwegian Petroleum Museum the following: the seabed in one piece. Basically, all installa- “The Directorate [..] will like the oil museum to tions on the field shall be removed when pro- draw up a systematic overview of large physi- duction ends. cal oil installations that may be preserved - on the spot, at museums or elsewhere.” So far the Save Draugen! There is no project launched to 37 phrase «large structures» has meant equipment save the platform for eternity. The Draugen field limited by size and weight up to 10 meters and/ is still producing at a daily rate of about 20 000 or 100 tons. An oil platform is of a completely barrels a day. The planning for abandonment has different magnitude. But on the other hand – no not officially started - yet. When I (as a private suggestions have ever been officially introduced person) have introduced the idea to different – maybe it’s about time! persons and authorities, they have all shaken their heads and called it crazy and impossible. 35 Why Draugen? The most unique feature from However, after having presented my case, the the Norwegian oil industry is the use of concrete skepticism has often turned into curiosity and platforms – Concrete Deepwater Structures, sometimes excitement. It all started during an Condeep. The Draugen is a concrete platform informal dinner meeting with representatives of and has also achieved an international award for the Directorate for Cultural Heritage of Norway. its design – The Golden Medal Gustav Magnel I started to investigate what were the rules and 1989 - 1994. Concrete technology that has been regulations for the UNESCO-list, and I discovered developed is also applicable to other geographic that it could be possible if one could get enough areas. Draugen was the first platform north of attention. I made a PowerPoint presentation and 62th latitude – an important limit politically. showed it to friends and historians. They were Indeed, the Norwegian oil industry’s expansion all very skeptical of the project, but since I am towards the north has contributed to the most an engineer by profession, I explained the tech- polarized conflict line in Norwegian oil policy. nology behind the idea (not thinking about the At the end of the 1970s, the battle was about money) and they were convinced by the project… whether to open the areas north of 62nd latitude One person said after having seen and heard my for oil drilling. From the 1970s, the opposition enthusiastic dream: It may be a dream – but was primarily between fisheries and conserva- the idea is crazy enough to actually be possible! tion interests on the one hand and industrial interests and a desire for local business devel- That has since been my guideline and I will spend 38 opment on the other. my first year in retirement following my dream! The seeds have been planted, but it still is a long 36 Draugen is one of the fields that has the high- way to go. The cost will be enormous and many est utilization rate on the Norwegian continental technical problems will have to be solved – but shelf (about 70%) - which is world-wide super 60 years ago nobody believed there was any oil league. The Draugen will probably shut down at all in Norwegian waters… production from the main reservoir within 10 JEHRHE #2 | ENERGY SOURCES P. 15

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Bibliography

Hauge Alfred Steen Øyvind Vaughan Adam Leviathan (Oslo: Gyldendal Norsk På dypt vann. Norwegian “Shell begins huge task of decom- Forlag, 1979). Contractors 1973 – 1993 (Oslo: missioning Brent oil rigs”, The Norwegian Contractors, 1993), Guardian, 06/02/2017. Measham Lea Frederick The Chemistry of Cement and Tønnesen Harald, Hadland Gunleiv Whitehouse Ruth, Wilkins John Concrete 3rd ed. (London: Arnold, Oil and Gas Fields in Norway. The Making of Civilization. History 1970). Industrial Heritage Plan (Stavanger: Discovered Through Archaeology Norwegian Petroleum Museum, (New York: Alfred A. Knopf, 1986). 2011).

Links

• http://www.norskolje.museum.no/en/home/oil-facts/publications/oil-and-gas-fields-in-norway/ • http://www.kulturminne-ekofisk.no/ • http://www.kulturminne-frigg.no/ • http://www.kulturminne-statfjord.no/ • http://www.kulturminne-valhall.no/ • https://draugen.industriminne.no/en/home/